WASHINGTON — President Barack Obama trumpeted two major endorsements for his health overhaul push Thursday as House Democratic leaders pushed toward a vote Saturday on the far-reaching legislation remaking the U.S. health care system.

"I am extraordinarily pleased and grateful to learn that the AARP and the American Medical Association are both supporting the health insurance reform bill that will soon come up to vote in the House of Representatives," Obama said in an unannounced visit to the White House briefing room.

AARP is "no small endorsement," Obama said of the 40-million strong seniors' lobby.

"We are closer to passing this reform than ever before," Obama said. "Now that the doctors and medical professionals of America are standing with us, now that the organizations charged with looking out for the interests of seniors are standing with us, we are even closer."

Obama spoke as House Democratic leaders sought to resolve final disputes before bringing their 10-year, $1.2 trillion health bill to the floor on Saturday. Majority Leader Steny Hoyer, D-Md., said leaders expect to have the 218 votes needed to pass the sweeping bill, which would extend coverage to tens of millions of uninsured people and ban insurance companies from turning people away.

Hoyer acknowledged the vote could be tight, though, and timing of action in the Senate remains uncertain.

"I wouldn't refer to it as a squeaker, but I think it's going to be close," Hoyer said in an interview with wire service reporters. "This is a huge undertaking."

The Maryland Democrat said language on abortion and illegal immigrants was still being worked out, but predicted those issues could be solved by Saturday.

"We certainly have well over 218 people who say they want to vote for the bill," Hoyer said.

"The trick is making sure they have a comfort level with the provisions they are particularly focused on to allow them to do so," he said.

Obama planned a rare trip to the House on Friday to try to win over wavering lawmakers.

House Speaker Nancy Pelosi denied that Obama's visit was needed to get Democrats over the top on the vote count. "We are thrilled that he is coming tomorrow, and we can have our conversation before we go into the process of bringing this legislation to the floor," the California Democrat told reporters at her weekly news conference.